THE EUSTACHIAN TUBE 311
of a grommet in the drumhead will give some symptomatic relief. Insuffla-
tion of an irritant powder, consisting of four parts of boric acid and one
part of salicylic acid, into the Eustachian tube was formerly recommended
as a means of obtaining temporary relief.
EUSTACHIAN TUBAL FOREIGN BODIES
The use of bougies for dilatation of the Eustachian tube accounted on some
occasions for a foreign body consisting of a part of the bougie which had
accidentally broken off and become lodged in the cartilaginous part of the
tube. Small foreign bodies perforating the tympanic membrane may pass
into the Eustachian tube and become lodged in the bony portion or at
the isthmus. Foreign bodies should be removed from the tube as soon as
possible. A surgical approach by a combined postauricular and transmeatal
route to the bony Eustachian tube has been described.
OTITIC BAROTRAUMA (AERO-OTITIS MEDIA)
Otitic barotrauma is related to the condition and patency of the Eustachian
tube in its function of ventilating the middle ear so that atmospheric pressure
pertains on both sides of the drumhead. Barotrauma follows rapid descent
in an aeroplane or, in high-speed aircraft, a very fast ascent. It may occur
in the presence of tubal dysfunction involving its patency and preventing
adequate ventilation of the middle ear in a situation which often arises
suddenly. Swallowing and yawning cause contraction of the tensor and
levator palati muscles which open the Eustachian tube thus allowing equal-
ization of pressure in the middle ear. Chewing of sweets or gum may there-
fore be advised as a preventive measure during descent. For those who have
previously suffered from the condition a decongestant nasal spray or a
benzedrine inhaler is a useful prophylactic measure. The symptoms of baro-
trauma vary from slight discomfort and feeling of fullness in the ear to
acute pain with effusion and deafness. Deafness and tinnitus may persist
after landing and inspection of the drumhead may show gross retraction
and congestion. Equalization of pressure is necessary at the earliest moment.
During descent the intermittent performance of Valsalva's manoeuvre may
be useful and later catheterization and inflation are often necessary. Many
cases settle spontaneously or with the help of conservative measures but
in a few cases myringotomy and aspiration of the effusion are necessary.
In the presence of an acute upper respiratory infection the risk of a suppura-
tive otitis media is increased and a prophylactic course of an antibiotic such
as penicillin is justifiable. In the majority of patients return of normal func-
tion may be expected.